How good are recent LCDs at non-native resolutions?
I'm considering replacing my old CRT with a 20" LCD but I'm not planning on changing CPU or graphics card soon, so my games would have to run at 1024x768 or so. Does that look too bad or is it acceptable?
I also play MAME and C=64 games sometimes so I'd need an even lower resolution to play full-screen.
If the aspect ratio of the new monitor is different than 4:3, then the pixels will not be square in 1024x768 which will give a somewhat fuzzy look.
It varies greatly depending on the LCD and the graphics card. I don't think there is any way to tell other than trying it.
After some research, I found out that some LCDs have a feature called 1:1 pixel mapping which allows non-native resolutions without stretching/scaling/interpolating the image, at the expense of screen estate.
I recently also learned that this can be done via graphics card drivers, i.e. in NVidia drivers it's called "flat panel scaling"
Emulators have the images upscaled in the computer to the native resolution of the LCD. I like them upscaled blocky to 5x5 pixel blocks, but you can also choose to use tridot emulation in software, to fake an old TV dot pattern. With vector games like Tempest or Star Wars high res LCD's are awesome!
With those 1024x768 games, it depends on your monitor. Some have a 1:1 pixel mapping feature, some have scaling in the native aspect ratio, some scale everything full screen independent of the original aspect ratio. With the best LCD's you can even choose some upscaling algoritms, but most LCD's scale a bit like bicubic scaling in Photoshop.
